1. Field of the invention
The present invention concerns a device for continuously detecting breathing rhythm, in particular, but not exclusively, with a view to preventing the sudden death of an infant due to apnea or stoppage of breathing during sleep.
It is widely recognized that apnea in an infant is currently the prime cause of death amongst children aged less than twelve months. This syndrome is still unexplained and there currently exists no effective means to prevent such deaths.
The only possible action that can be taken, especially as regards the prevention of recurrences, consists of continuous cardiorespiratory surveillance of the child whilst it is asleep so as to be able to detect if breathing has stopped, and, where this continues, to proceed with elementary first-aid measures such as jlts, artificial respiration or even,in certain cases, external cardiac massage. Owing to the fact that this syndrome can occur after only several minutes of sleep, it is necessary, if one desires to exclude any possibility of accident, to keep the infant under twenty-four surveillance.
Consequently, as regards the current state of the technique, for such surveillance to be fully effective, it needs to be provided in a hospital centre using quite expensive equipment requiring the constant presence of a medical assistant. Now, the time the infant spends in the hospital centre is often insufficient to eliminate every risk, all the more so because the decision to stop continuous surveillance is usually difficult to take owing to the lack of formal criteria for eliminating risks.
2. Description of the prior art
With the aim of overcoming these drawbacks, devices have already been proposed enabling breathing surveillance of an infant to be carried out in the home. These devices usually appear in the form of an electronic box or "monitor" connected by linkage, e.g. pneumatic or electronic, to one or more detectors intended to be attached to the body of the infant or in close proximity to the latter.
However, a first drawback of these devices, apart from the fact that they are still expensive, is that the links between the monitor and the child make them awkward to use, especially when dressing, undressing or moving the infant. In addition, the fact of the infant moving may result in the connections being pulled and consequently the sensors being moved or damaged, thus rendering them ineffective which could set off false alarms.
A second drawback is that the sensors and possibly their links to the electronic box must be regularly changed and this makes the device more expensive to use.
A third drawback originates from the fact that, with a view to permitting surveillance, these devices usually produce light impulses and/or sound impulses (bips) in synchronism with the child's breathing rhythm. As a result, even in the case where they include means allowing an alarm signal to be generated (generally a sound signal) indicating absence of breathing exceeding a predetermined period, they require the continuous presence of someone in the immediate proximity of the device.